/*!	 valuenode_timedswap.cpp
**	 Implementation of the "Timed Swap" valuenode conversion.
**
**	Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
**	Copyright (c) 2007, 2008 Chris Moore
**  Copyright (c) 2011 Carlos López
**
**	This package is free software; you can redistribute it and/or
**	modify it under the terms of the GNU General Public License as
**	published by the Free Software Foundation; either version 2 of
**	the License, or (at your option) any later version.
**
**	This package is distributed in the hope that it will be useful,
**	but WITHOUT ANY WARRANTY; without even the implied warranty of
**	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
**	General Public License for more details.
**
*/

#ifdef USING_PCH
#	include "pch.h"
#else
#ifdef HAVE_CONFIG_H
#	include <config.h>
#endif

#include <synfig/general.h>
#include <synfig/localization.h>
#include <synfig/valuenode_registry.h>
#include "valuenode_timedswap.h"
#include "valuenode_const.h"
#include <stdexcept>
#include <synfig/color.h>
#include <ETL/misc>

#endif

using namespace std;
using namespace etl;
using namespace synfig;

REGISTER_VALUENODE(ValueNode_TimedSwap, RELEASE_VERSION_0_61_07, "timed_swap", "Timed Swap")

ValueNode_TimedSwap::ValueNode_TimedSwap(const ValueBase &value):
    LinkableValueNode(value.get_type())
{
    Vocab ret(get_children_vocab());
    set_children_vocab(ret);
    Type &type(get_type());

    if (type == type_angle) {
        set_link("before", ValueNode_Const::create(value.get(Angle())));
        set_link("after", ValueNode_Const::create(value.get(Angle())));
    } else if (type == type_color) {
        set_link("before", ValueNode_Const::create(value.get(Color())));
        set_link("after", ValueNode_Const::create(value.get(Color())));
    } else if (type == type_integer) {
        set_link("before", ValueNode_Const::create(value.get(int())));
        set_link("after", ValueNode_Const::create(value.get(int())));
    } else if (type == type_real) {
        set_link("before", ValueNode_Const::create(value.get(Real())));
        set_link("after", ValueNode_Const::create(value.get(Real())));
    } else if (type == type_time) {
        set_link("before", ValueNode_Const::create(value.get(Time())));
        set_link("after", ValueNode_Const::create(value.get(Time())));
    } else if (type == type_vector) {
        set_link("before", ValueNode_Const::create(value.get(Vector())));
        set_link("after", ValueNode_Const::create(value.get(Vector())));
    } else {
        throw Exception::BadType(type.description.local_name);
    }

    set_link("time", ValueNode_Const::create(Time(2)));
    set_link("length", ValueNode_Const::create(Time(1)));
}

ValueNode_TimedSwap*
ValueNode_TimedSwap::create(const ValueBase& x)
{
    return new ValueNode_TimedSwap(x);
}

LinkableValueNode*
ValueNode_TimedSwap::create_new()const
{
    return new ValueNode_TimedSwap(get_type());
}

synfig::ValueNode_TimedSwap::~ValueNode_TimedSwap()
{
    unlink_all();
}

synfig::ValueBase
synfig::ValueNode_TimedSwap::operator()(Time t)const
{
    if (getenv("SYNFIG_DEBUG_VALUENODE_OPERATORS")) {
        printf("%s:%d operator()\n", __FILE__, __LINE__);
    }

    Time swptime = (*swap_time)(t).get(Time());
    Time swplength = (*swap_length)(t).get(Time());

    if (t > swptime) {
        return (*after)(t);
    }

    if (t <= swptime && t > swptime - swplength) {
        Real amount = (swptime - t) / swplength;
        // if amount==0.0, then we are after
        // if amount==1.0, then we are before

        Type &type(get_type());

        if (type == type_angle) {
            Angle a = (*after)(t).get(Angle());
            Angle b = (*before)(t).get(Angle());
            return (b - a) * amount + a;
        } else if (type == type_color) {
            Color a = (*after)(t).get(Color());
            Color b = (*before)(t).get(Color());
            // note: Shouldn't this use a straight blend?
            return (b - a) * amount + a;
        } else if (type == type_integer) {
            float a = (float)(*after)(t).get(int());
            float b = (float)(*before)(t).get(int());
            return round_to_int((b - a) * amount + a);
        } else if (type == type_real) {
            Real a = (*after)(t).get(Real());
            Real b = (*before)(t).get(Real());
            return (b - a) * amount + a;
        } else if (type == type_time) {
            Time a = (*after)(t).get(Time());
            Time b = (*before)(t).get(Time());
            return (b - a) * amount + a;
        } else if (type == type_vector) {
            Vector a = (*after)(t).get(Vector());
            Vector b = (*before)(t).get(Vector());
            return (b - a) * amount + a;
        }
    }

    /*! TODO:  this should interpolate from
    **	before to after over the period defined
    **	by swap_length */

    return (*before)(t);
}

bool
ValueNode_TimedSwap::set_link_vfunc(int i, ValueNode::Handle value)
{
    assert(i >= 0 && i < link_count());

    switch (i) {
    case 0:
        CHECK_TYPE_AND_SET_VALUE(before,      get_type());

    case 1:
        CHECK_TYPE_AND_SET_VALUE(after,       get_type());

    case 2:
        CHECK_TYPE_AND_SET_VALUE(swap_time,   type_time);

    case 3:
        CHECK_TYPE_AND_SET_VALUE(swap_length, type_time);
    }

    return false;
}

ValueNode::LooseHandle
ValueNode_TimedSwap::get_link_vfunc(int i)const
{
    assert(i >= 0 && i < link_count());

    switch (i) {
    case 0:
        return before;

    case 1:
        return after;

    case 2:
        return swap_time;

    case 3:
        return swap_length;
    }

    return 0;
}

bool
ValueNode_TimedSwap::check_type(Type &type)
{
    return
        type == type_angle	||
        type == type_color	||
        type == type_integer	||
        type == type_real 	||
        type == type_time 	||
        type == type_vector;
}

LinkableValueNode::Vocab
ValueNode_TimedSwap::get_children_vocab_vfunc()const
{
    if (children_vocab.size()) {
        return children_vocab;
    }

    LinkableValueNode::Vocab ret;

    ret.push_back(ParamDesc(ValueBase(), "before")
                  .set_local_name(_("Before"))
                  .set_description(_("The value node returned when current time is before 'time' - 'length'"))
                 );

    ret.push_back(ParamDesc(ValueBase(), "after")
                  .set_local_name(_("After"))
                  .set_description(_("The value node returned when current time is after 'time'"))
                 );

    ret.push_back(ParamDesc(ValueBase(), "time")
                  .set_local_name(_("Time"))
                  .set_description(_("The time when the linear interpolation ends"))
                 );

    ret.push_back(ParamDesc(ValueBase(), "length")
                  .set_local_name(_("Length"))
                  .set_description(_("The length of time when the linear interpolation between 'Before' and 'After' is made"))
                 );

    return ret;
}